It is speculated that the flat stucco roofs on the schools, a popular design in the American Southwest, cracked and led to water leakage and eventually mold, the story stated.

Tony Malaj, Higley Unified School District director of student services, said: "[An indoor air quality] test showed there was no airborne mold. The problem is we have two other schools with similar designs, which may have similar issues."

The district plans to have more air quality tests done in the following weeks to either confirm or dispel the presence of mold in Power Ranch and Coronado and take the necessary steps to remediate the problem, the story noted.

According to the Federal Emergency Management Agency (FEMA), continued exposure to mold may result in nasal or sinus congestion, eye, nose or throat irritations and adverse effects to the nervous system.

Power Ranch Elementary had a previous mold problem and the district believed they properly addressed maintenance issues that led to the contamination, the story added.